Chosen Solution

My phone is intermittently going bezerk! It opens apps, dials contacts, types nonsense without being touched! I have tried a new battery, restarting the phone, opening in safe mode and doing a factory reset. Would it be a hardware issue, and can it be fixed?

It is probably the digitizer doing all this crazy stuff. Your phone is not possessed, no need to call the neighborhood medium! I will provide you a link to the part and a link to the iFixit repair guide below. LG G4 Screen and Digitizer Assembly iFixit repair guide